(1) Field of the Invention
The present invention relates to a method and apparatus for jetting auxiliary fluid to a fluid and filling guide passage formed on a sley in a jet loom.
(2) Description of the Prior Art
There is known a filling apparatus in which, in order to maintain a sufficient flying force in wefts filled by a fluid jetted from a main nozzle toward a guide passage formed on a sley, an auxiliary fluid is jetted from auxiliary nozzles disposed so as to confront the guide passage at predetermined intervals. Ordinarily, one round hole directed to the guide passage is formed as a jet opening of the auxiliary nozzle for jetting an auxiliary fluid. Furthermore, there is known an auxiliary nozzle in which a great number of fine holes are formed a range of a round area instead of the above-mentioned round hole, so that the angle of the jetting of a fluid from this auxiliary nozzle is set as close to right angle to the longitudinal axis of this auxiliary nozzle as possible, as disclosed in Japanese Patent Application Laid-Open Specification No. 17368/1976.
In the above-mentioned known auxiliary fluid jetting nozzles, in order to improve the utilization efficiency of the fluid, that is, to obtain a necessary jet speed with a minimum consumption of power, an attempt has been made to reduce the diameter of the opening as much as possible. In such conventional auxiliary fluid jetting apparatus, however, when a weft is caused to fly in the guide passage formed on the sley, since the region where the auxiliary fluid works in the perpendicular direction to the guide passage, particularly, the fluid operating zone just downstream of the fluid jetting point is narrow, the weft tends to run through a region where the action of the auxiliary fluid is relatively weak and escape from the guide passage. Accordingly, it often happens that the weft does not undergo the action of the auxiliary fluid and the weft speed is reduced, and in the worst case, the weft running away from the guide passage is caught on the auxiliary nozzle to render the filling operation impossible. In short, the conventional auxiliary fluid jetting apparatus has a defect in that the stability of the filling operation is extremely bad.
If only the fluid zone corresponding to the guide passage is taken into account, it would appear that the above mentioned problem regarding the auxiliary nozzle could be solved by increasing the diameter of the jetting opening. However, if the diameter of the jetting opening is increased, another defect is caused in that the power consumption is greatly increased. More specifically, since the flow rate of the fluid is lowered as the diameter of the jetting opening is increased, the jetting pressure must be elevated to obtain a predetermined flow rate of the fluid. Moreover, a great number of auxiliary nozzles are arranged in the filling direction and, since these auxiliary nozzles are continuously operated while the loom is driven, an increase of the power consumption cannot be avoided.
As will be apparent from the above-mentioned discussion, in a loom in which auxiliary nozzles are arranged to confront a guide passage mounted on a sley and effect the filling operation, attainment of a stable filling operation is directly related to an increase of the power consumption in an auxiliary fluid jetting apparatus and there are included contradictory problems to be solved in attaining a stable filling operation.